Express Cloud Foundry Actuator Middleware

1.8.0 verified Fri May 01 auth: no javascript maintenance

Express middleware providing health and info endpoints for Cloud Foundry Apps Manager, inspired by Spring Boot Actuator. Current stable version is 1.8.0 (released May 2021), with maintenance-level updates addressing dependency vulnerabilities. Key differentiators: integrates natively with Cloud Foundry's Apps Manager UI, restricts endpoints to authenticated/authorized users, and works with the companion CLI to generate build info files. Compatible with Node 6+ (legacy engine requirement). Provides only health and info endpoints (no metrics, environment, or other Spring Boot actuator endpoints). Last release was over 3 years ago; no active development expected.

Common errors

error TypeError: actuator is not a function ↓

cause actuator is imported as a default export but the package uses module.exports with a factory function.

fix

Use const actuator = require('express-cloudfoundry-actuator-middleware'); then call app.use(actuator());

error Cannot find module 'express-cloudfoundry-actuator-middleware' ↓

cause The package was not installed, or installed in the wrong directory.

fix

Run npm install express-cloudfoundry-actuator-middleware --save in your project root.

error Route.get() requires a callback function but got a [object Object] ↓

cause actuator() returns an object with router functions, but it's not a direct middleware; calling actuator() without using it in app.use() leads to this error.

fix

Ensure you use app.use(actuator()) and not app.get('/', actuator()).

Warnings

gotcha The actuator middleware must be used before other routes to ensure endpoints are accessible. ↓

fix Place app.use(actuator()) before route definitions.

gotcha Options object is required; passing no arguments or undefined will still enable default endpoints, but any additional configuration must be passed explicitly. ↓

fix Use actuator({ health: true, info: true }) to explicitly enable endpoints.

gotcha The 'info' endpoint requires a build info file generated by Cloud Foundry Actuator CLI; without it, the endpoint may return empty or error. ↓

fix Run the CLI tool before deployment: npx cloudfoundry-actuator-cli build-info

deprecated Node engine requirement is >=6, which is end-of-life. The package may not work on modern Node versions (>=18) without compat flags. ↓

fix Use Node 16 or lower, or consider using the '--openssl-legacy-provider' flag if needed.

Install

npm install express-cloudfoundry-actuator-middleware

yarn add express-cloudfoundry-actuator-middleware

pnpm add express-cloudfoundry-actuator-middleware

Imports

default

wrong

import actuator from 'express-cloudfoundry-actuator-middleware'

correct

const actuator = require('express-cloudfoundry-actuator-middleware')

The package is CommonJS only; ESM import will fail.

actuator
wrong
```
app.use(actuator)
```
correct
```
app.use(actuator())
```
actuator is a factory function that returns middleware; must be called.

options

wrong

app.use(actuator({ endpoints: ['health','info'] }))

correct

app.use(actuator({ health: true, info: true }))

Options are booleans, not an array; see README for full options.

Quickstart

Sets up an Express app with the actuator middleware, enabling health and info endpoints for Cloud Foundry.

const express = require('express');
const app = express();
const actuator = require('express-cloudfoundry-actuator-middleware');

// Optional: configure endpoints
const options = {
  health: true,
  info: true
};

app.use(actuator(options));

app.get('/', (req, res) => res.send('Hello World!'));

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => console.log(`App listening on port ${PORT}`));